﻿using System;
using System.Globalization;
using System.Windows;
using System.Windows.Data;

namespace Foundation.Converters
{
    /// <summary>
    /// Visibility Converter.
    /// </summary>
    public class VisibilityConverter : IValueConverter
    {
        /// <summary>
        /// Gets or sets the on hidden.
        /// </summary>
        /// <value>
        /// The on hidden.
        /// </value>
        public object OnHidden { get; set; }

        /// <summary>
        /// Gets or sets the on visible.
        /// </summary>
        /// <value>
        /// The on visible.
        /// </value>
        public object OnVisible { get; set; }

        /// <summary>
        /// Gets or sets the on collapsed.
        /// </summary>
        /// <value>
        /// The on collapsed.
        /// </value>
        public object OnCollapsed { get; set; }

        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value produced by the binding source.</param>
        /// <param name="targetType">The type of the binding target property.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value == null) return null;
            if (value.Equals(Visibility.Hidden)) return OnHidden;
            if (value.Equals(Visibility.Visible)) return OnVisible;
            if (value.Equals(Visibility.Collapsed)) return OnCollapsed;
            return null;
        }

        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value that is produced by the binding target.</param>
        /// <param name="targetType">The type to convert to.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value == null) return null;

            if (string.Compare(
                value.ToString(),
                OnHidden == null ? string.Empty : OnHidden.ToString(),
                StringComparison.OrdinalIgnoreCase) == 0)
                return Visibility.Hidden;

            if (string.Compare(
                value.ToString(),
                OnVisible == null ? string.Empty : OnVisible.ToString(),
                StringComparison.OrdinalIgnoreCase) == 0)
                return Visibility.Visible;

            if (string.Compare(
                value.ToString(),
                OnCollapsed == null ? string.Empty : OnCollapsed.ToString(),
                StringComparison.OrdinalIgnoreCase) == 0)
                return Visibility.Collapsed;

            return null;
        }
    }
}
